The endless carrier is constructed from a flexible metal band such as steel with a row of uniformly spaced engraved type characters and one or more rows of indicia marks. The indicia marks are designed for sensing by emitters while the type band is revolved relative to a row of print hammers which strikes a print medium against the type characters. The drive system for revolving the metal band at constant speed commonly comprises a pair of spaced rotatable pulleys one of which is a drive pulley and the other an idler pulley. The endless type band is partially wrapped around the pulleys in tension so as to be driven by contact friction of the drive pulley. A platen of metal or other hard material is located between the pulleys behind the metal band on the side opposite the print hammers. The platen resists displacement of the type band when struck by the hammers. A wear strip of thin plastic material is provided between the metal band and the platen. The wear strip acts as a barrier to prevent rapid wearing of the type band. The continuous sliding contact of the type band on the wear strip punctuated by the frequent impacts of the hammers causes the strip to wear to the point where it must be replaced. In wearing, residue from the wear strip adheres to the type band and along with other debris from the print medium becomes deposited on the drive surfaces of the pulleys. The deposits can build up in a more or less irregular pattern on the drive surface to the point where the path of travel of the type band is changed sufficiently to affect band tracking, print quality and may cause emitter damage. Prior attempts at correcting the problem have involved cleaning the type band. However, cleaning the type band does not effectively prevent buildup and causes band alignment and band wear problems and made it difficult and cumbersome to service and maintain the wear strip and cleaning mechanisms of the printer apparatus.